The invention relates to packaged dental compositions and methods of use thereof. The invention provides a storage stable packaged dental composition having one or more volatile components and methods of use thereof. In accordance with the invention there is provided a storage stable packaged dental compositions having one or more volatile components such a polar organic solvent and/or low molecular weight monomer.
One major problem with prior art injection molded packaging of dental compositions having one or more volatile components is the loss of a major portion of the volatile components from the dental compositions during storage. When the stored dental compositions with effectively reduced volatile components are used the originally available results are not provided. Thus, for example, dental adhesive and/or primer compositions stored in prior art injection molded packaging loose much, if not all, of their capacity for adhesion and/or priming. Other problems with prior art injection molded packaging of dental compositions include weight decrease of the polymeric material while enclosing the dental composition due to diffusion of components of the polymeric material from the polymeric material, and may cause contamination of the dental composition by components of the polymeric material. A weight increase of the polymeric material while enclosing the dental composition may be due to infusion of water from ambient humidity and/or solvent (or other components) from the polymeric material. Thus a weight increase of the polymeric material may be indicative of a loss of solvent from the dental composition and/or water contamination of the dental composition. When the stored dental compositions (with effectively contaminated and/or depleted components) are used, the originally available results are not provided. These problems of prior art injection molded packaging of dental compositions are solved by the present invention.
To ensure proper functioning of dental materials, they need to be protected from undergoing changes during storage. These changes of material may occur if external substances (e.g. moisture) penetrate the dental materials, or if parts of the dental materials (e.g. solvents) evaporate or otherwise diffuse off. Therefore a suitable packaging is needed to prevent both intrusion of moisture into the dental materials and evaporation of solvent or other vital parts of the dental materials. Several ways of packaging have been tried, mostly using laminate materials consisting of different polymers. However, particularly for very small containers of dental materials (e.g. single unit dosage containers), laminate materials are not a viable solution as they are too difficult to shape and process.
It is an object of the invention to provide a storage stable dental composition such as one containing a volatile organic solvent and a polymerizable material enclosed by a package,which includes a cover and a container.
It is an object of the invention to provide a stored packaged dental product by the process including: enclosing a dental composition in a package with at least a substantial portion of an injection molded polymer, and storing the dental composition in the package for at least 1 week.
It is an object of the invention to provide a stored packaged dental product by the process comprising: enclosing a dental composition including a volatile organic solvent in a package, at least a substantial portion of the package comprising a polymer having a high chemical resistance and barrier capability toward polar organic solvents and water. After storing the dental composition in the package for at least two weeks at 37xc2x0 C. at least 50 and more preferably 75 or even 90 percent of the volatile organic solvent remains in the package.
As used herein open chain olefins are noncyclic olefins and include linear open chain olefins, straight chain olefins, branched chain olefins and branched open chain olefins. Open chain olefins are not closed chain olefins or ring olefins. Linear open chain olefins are most preferred open chain olefins for use in making copolymer for use in accordance with the invention.
As used herein volatile component refers to a component (of a dental composition) having vapor pressure more than that of water at 20xc2x0 C.
As used herein volatile polar solvents refers to polar solvents, such as water, ethanol and acetone, which are at least as volatile as water at 20xc2x0 C.
As used herein volatile organic solvents refers to organic solvents, such as ethanol and acetone, which are more volatile than water at 20xc2x0 C.
As used herein moderately volatile organic solvent refers to an organic solvent, such as ethanol, which is more volatile than water, but not more volatile than ethanol i.e. vapor pressure more than that of water at 20xc2x0 C., but less than or equal to 43 mm Hg at 20xc2x0 C.
As used herein very volatile organic solvent refers to an organic solvent, such as acetone, which is more volatile than ethanol i.e. vapor pressure more than 43 mm Hg at 20xc2x0 C.
As used herein high permeability barrier capability for water (and high water barrier capability) refers to polymeric material having a water vapor permeability below 0.07 g (mm)(mxe2x88x922)(dxe2x88x921) measured by DIN 53122 at 23xc2x0 C. and 85 percent relative humidity.
As used herein high penetration barrier capability for solvent of a polymeric material toward polar organic solvents refers to less than 2 percent by weight loss of polar organic solvents from a composition having at least 5 percent by weight of polar organic solvent(s) while enclosed in the polymeric material for at least two weeks at 37xc2x0 C.
As used herein very high penetration barrier capability for solvent of a polymeric material toward polar organic solvents refers to less than 0.5 percent by weight loss of polar organic solvents from a composition having at least 5 percent by weight of polar organic solvent(s) while enclosed in the polymeric material for at least two weeks at 37xc2x0 C.
As used herein high penetration barrier capability for water of a polymeric material toward water and humidity refers to a less than 3 percent by weight increase of a composition due to infusion of water through the polymeric material while the composition is enclosed in the polymeric material for at least two weeks at 37xc2x0 C.
As used herein very high penetration barrier capability for water of a polymeric material toward water and humidity refers to a less than 1 percent by weight increase of a composition due to infusion of water through the polymeric material while the composition is enclosed in the polymeric material for at least two weeks at 37xc2x0 C.
As used herein high chemical resistance of polymeric material refers to polymeric material having both a less than 3 percent by weight increase of the polymeric material, and a less than 0.5 percent by weight decrease of the polymeric material while the polymeric material is immersed in water and/or solvent for at least two weeks at 37xc2x0 C. A weight decrease of the polymeric material while enclosing a dental composition (and/or immersed in water and/or solvent) may be due to diffusion of components of the polymeric material from the polymeric material, and may cause contamination of the dental composition by components of the polymeric material. A weight increase of the polymeric material while enclosing a dental composition and/or immersed in water and/or solvent may be due to infusion of water and/or solvent into the polymeric material, and may indicate that the polymeric material allows loss (or gain) of solvent from the dental composition and/or water contamination of a dental composition.
As used herein low molecular weight monomer refers to an acrylic monomer, such as methyl methacrylate having a gram molecular weight less than 150.
As used herein single unit dosage refers to volumes of a dental composition between 0.01 and 1 ml.